updated deps and code to a more recent state

build.gradle

@@ -15,13 +15,13 @@
  * You should have received a copy of the GNU General Public License
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  */
-// Top-level build file where you can add configuration options common to all sub-projects/modules.
+
 buildscript {
     repositories {
         jcenter()
     }
     dependencies {
-        classpath 'com.android.tools.build:gradle:2.1.0'
+        classpath 'com.android.tools.build:gradle:2.2.3'
     }
 }